diff --git a/.travis.yml b/.travis.yml
index 789adcbe38d..12e4da4a30f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -9,6 +9,7 @@ build: &rust_build
     rust: 1.31.1
     script:
         - rustup component add rustfmt
+        - rustup component add rust-src
         - cargo gen-tests --verify
         - cargo gen-syntax --verify
         - cargo test --no-run  # let's measure compile time separately